Locomotive valve-gear.



I. HWESJR.

LOCDMOHVE VALVE GEAR.

vvucmnu FILED math. 1917.

Patented May- 15, 1917.

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INVENTOR WITNESS ATTo R N EY T. JAMES, M, LUCOMOTIVE VALVE GEAR.

APPLICATION FILED FEB. 2!, 1917 1 ,226,523. Y Patented Ma 15,1917"..

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A I VENT'Q W'TNESS 1720mm? Jar/may]? ATTORNEY rnoivias James, .73., orPHILADELPHIA, rnNnsYLjvAm'jm LocoMorxvn VALVE-GEAR).

Specification of Letterslatent.

Application filed February 21, 1917. Serial No. 150,101.

To all whom it may concern Be it known that i, TI-IO'M'AH JIABIES, Jr.,a.

citizen of the lllnited States, i or. ng at 403 lielmont Apartnnn flhn vhearth and bprlng Garrilen SlI-I'QQlI-F-J, lhih lolphia, in the "countyof Philadelphia and State of Penn 'sylvanla', have invented newand-useful Improvements in Locomotive Valve-Gears, of

' which the followin is a specification.

Thisinvention IBTEItGS to im1n'ovemen.ts in valve gears, and hasparticular reference to a. valve gear for use in connection with theusual reciprocatingpiston valves ofthe type now commonly em.1;nlo' \;'edin locomotive en-- ginesg One of the main objects of the inventionresides in a. valve gear of peculiar constructlon and operation foreffecting the operatin'g movements of a steam distribution valve of a.locon'mtive engine, said gear being adapted to operate the valve toeffect an acceleratd opening and closing of the steam ports governedthercby, and at the same time to permit of an extended open period ofsaid ports, in order that a prolonged expansion ofstearn, admitted. bysaid ports into a cylinan, will'he obtained, together with greatlydecreased exhaust compression.

helriniportant object of: the invention reside "providing a valve gearhaving adjumbl .catures of construction which will permit the lap andlead movements of the "steam distribution valve to be readilycontrolled, thus permitting the engine, with "which the valve gear isassociated, to be readily and easily started in a gradual manner, andwithout unnatural jolting' or jarring. A'further object of the inventionresides in a valve gear possessing the above character-ifstics, whichwill be positive and eflicient in: operation, not liable to become outof orderadjustment, and to permit the engine asso. ated therewith to bemore economically operated;

Other objects will be in part obvious and in part pointedi'outhereinafter. i To this and other useful ends, the invention'consists offeatures hereinafter set forth and claimed.

In the accompanying drawings Figure 1 is a diagrammatic side elevatlonof the valve gear embracing the principles of the present invention, thesame being 55 shown as applied to-a locomotlve steam engine, parts ofthe latter being broken away to disclose the underlying construction,the valve gear being shown in a. neutral or out of gear position. Fig.2' is asimilar view showing the valve gear, disclosing the same in itsextreme for ward position. 1 Fig. 3 is a transverse vertical alongtheline 3- 3 of Fig. 1. Fig. 4-is a horizontal sectional along the'linc4-4ofFig. 1.

section taken view taken i Patented- May 15,1917.

Fig. 5 is a similar "view,- the plane of which being disclosed b y theline 5-45 of ig 6 is an enlarged horizontal sectional view taken througha portion of the mechanism. disclosed in Fig. 5.

Fig. 7 is a. detail vertical sectional view taken through a disclosed inFig. 5.

Fig. 8 is a diagrammatic view illustrating the relative positionso'fESthe distribution valve, radius rod, combination lever, and thecooperating crosshead, when the latter is moving in the direction of thearrow, and

Fig. 9 is a similar view disclosing the positions of the partsenumerated in Fig. 8 when the crosshead is reciprocating in the oppositedirection.

Similar characters of reference denote corresponding parts throughoutthe several figures of. the drawings.

.Referring to the drawings by numerals, the valve gear comprising thepresentinvention, is shown asemployed in connection with a locomotiveengine 1, consisting ofa cylinder 2, piston 3, steam distribut-ion valve4, and steam ports 5. The valve 4 in this instanceiis of the usualpiston valve type, and is constructed to permit of inside admission ofsteam into the cylinder 2.

The piston 3 is connected by means of a. piston rod 6 to a slidingcrosshead 7, mounted in fixed guides 8, rod 9 is pivotally connectedwith the crosshead, and is swivelcd as at 10 to one of the drivingwheels 11 of the-locomotive. A return crank .12 rotatable with the wheel11, has pivotally connected to' of the valve e, whereby the forward,rear-- portion (of the mechanism and a pitmanhard or neutral (positionsof the valve gear may be controlle To adjust the rod within the link, abell crank 18 is provided, said crank having oneof the arms thereofmovabl connected with one end of the radius rod? and the other endconnected with a manually controlled rod 19, whereby the said end of theradius rod may be ad usted to different positions within said reverselink. The above parts are of the usual construction in operation,therefore, a more extended explanation relative thereto will b omitted.

Secured in any simple manner to the crosshead 7 is a plate 20, thelatter being.

provided with an extended bifurcated extremity 21 in which is secured,by mechanism to be hereinafter fully described, the lower extremity of acombination lap and lead and cut elf lever 22. The latter e'xtendsupwardly to a position substantially in axial alinement with the valve4, and 15 connected with said valve through the provision of anelongated slot 23, formed in the lever 22. Mounted in the slot is areciprocating block 24, through which a p 1n 25 passes, the latterhaving its extremities fixed 'in the bifurcated end 26 of a slldmgcrosshead 27, which is mounted in fixed guide -protruding from thecaslng of the engine .1. The crosshead 27 is suitably conthe directionsindicated by the arrows.

nected with the outer end of a valve stem 28, extending from thedistribution valve in order that the reciprocating movements of thecrosshead 27 willbe synchronously imparted to said valve. It will benoted that the lower end of the lever 22, where'it is connected w th theplate 20, will move on a plane parallel to the direction of movement ofthe crosshead 7 and by the use of the slot and block connection 23 and24, a peculiar movement will be imparted to the valve 4 so as .to effectthe above stated objects- The outer end of the radius rod 17 ispivotally connected with the upper extremityofthe lever-22, at a ointabove the block 24, said rod, in this instance, being employed toregulate the distance between the pin 25 and the point of pivotalconnection between the rod 16 and the combination lever 22, whereby theout of gear or in ear positions of the valve gear will be obtainable. I

At this juncture attention is directed to the diagrammatic viewsillustrated in F 1gs. 8 and 9 of the drawings, which plainly'disclosethe. movements of the distribution valve 4, when the crosshead7 is moving 1in 11 these views the line A represents the direction. oftravel of the valve, the line B the movement of the crosshead, .and theobliquely directed line C the various positions the lever 22 will assumewhen in o eration,

the upper ends of"the line C iridlcate the curve or path of travel ofthe forward extremlty of the radius rod 17 Thus in Fig.

8, where the line C intersects the line A,

the valve 4 will be in a line and line position closing the ports 5, butwhen the crosshead travels a relativel short distance. to the positionindicated y the line G the valve 4 will be quickly reciprocated toeffect a complete opening of the port, so that the cylinder 2 w llreceive an unobstructed flow of steam, and to simultaneouslypermit of afull and free exhaust of the spent steam reason of this substantiallyrapid, or in-' termitteut movements of the valve, together with theprolonged openmgof the ports 5,

ma) be briefly stated as follows: firstly, th

quick admission of steam into'thecylinder, effected from the rapidopening of the ports; secondly, the prolonged period of steam expansion;thirdly, the extended open position of the ports when steam is beingexhausted therethrough, so as to eliminat -the back pressure upon thepiston.

Cooperating with the valve reciprocating mechanism, above described, isa variable lead controlling device for regulating the admission of steaminto'the cylinder 2. As is well known. in the ordinary VVals'chaertvalve the lead remains constant. which is exceedingly objectionable whenthe engine;

is being initially started. this being due to thefact that steam isadmitted into the cylinderan instant beforethe piston reaches theextremity of its stroke. thus causing a back pressure upon the slowlymoving piston, which is a distinct detriment to the successful start ofthe engine. However,

the constant lead operates very eflicaciouslywhen the engine is runningat full speed. For example, this action may be likened to the operationof an internal combustion mos tor.'when first started the spark foreffecting. the explosions of the mixture within its cylinders isretarded, so that the explosion will not take place until the piston ison a down stroke. But after the engine gathers momentum the spark isadvanced until the explosions created thereby occur just before thepiston reaches the end of" its lip-strokes. Therefore. the variable leaddevice utilized by the present invention, presents means for regulatingthe movement of the valve 4 so that when the engine 1 is beinginitiallystarted, steam will be admitted plate 20. A crank 33 issecured to oneend cylinders will take placejust before said pis-- into the cylinderimmediately subsequent to the period when the piston reaches theextremity of its movement. And further pro-- vides manually controlledmeans for shifting the valve, after the starting of the engine, so thatthe admission of steam into its ton arrives at its stroke extremities.

To effect this object the lower end o'fthe lever 22 is 'provided'with acircular opening in Which is positioned an eccentric 30,.the

latter being provided with a squared opening for the reception of, as'imilarlyshaped portion 31 of a shaft 32, which is iournaled forrotation in the bifurcated end 21 of the of the shaft 32, and has itsfree extremity pivotally connected .with a link 34, the other end ofsaid link being jointedas at'35 to a cocpe'rating link 36pivotally-carried by the plate 20. Connected with the links -3 l and s36 is a variable lead arm 37- the latter extending parallel with thelever 22, andhas its upper end swiveled to the radius rod 17, at aposition contiguousto the joint existing between said rod and the lever22'. It will be noted by reference to Figs. 1 and 2 that the combinationlever and the arm 37 will extend in parallel relation; regardless ofthe-position of the crosshead, this being due to the block and slotconnection utilized in associating said lever with the crosshead 27. I

In conclusion, it is-obvious that when the radius bar 17 is shifted tovary the cut-01f,

the link 27 pulls the eccentric 30 by means ofits connection therewithto cause the combination lever 22 to be'raised in order that the leadwill'be progressively increased with the cut-off." It is due to the"adjustment of the rod 17 which causes the lead' to 'change,i

" the lead remaining constant after the adjustment is made. i

From the 'foregoing it will be the objects of the invention have. beenachieved, and that all of the advantageous features above mentioned are,among others, present. The gear described may be readily attached, ifdesirable, upon any locomotive embracing the sliding piston valveconstrue tion, with but a minimum of cost and dlfii- Seen that there isprovided mechanism through which culty. The construction of the gear. byreason of its'simplified nature, willfenable the same to be absolutelyreliable'in o ration, and ,not likely to becomeout of or r, or torequire constant attention and adjustment.

Moreover, theinvention does not employ any extra levers to enable theengineer of a locomotive to regulate its several positions, but isautomatically operated by the usual reverse lever, common to alllocomotives.-

Having described the invention what is claimed-as new and patentable is:

1. In valve gear of the class described, the combination with an engineincluding a reciprocating piston valve and crosshead, a

plate secured to the crosshead, articulated links pivotally connectedwith said plate, an eccentric carried by the latter and having thepositions thereof regulated by said links,

of a lap and lead lever havjpg the substantia'lly lower extremitiesthereofrovided with an opening for the reception 0 said 'eccentric,wherebysaid lever will be capable of lllOVlIlgJH unlson with saldcrosshead, a

radius rod connected with the upper extremity of said lever, a stemprotruding from the valve and having a block and slot connection withsaid lever, and a variable lead controllingarm connected with saidradius rod and with said links at a position contiguous to said'leverand adapted. to maintain substantially parallel relation with thelatter, irrespective of the positions of said croshead..

2. In valve gear of the class described, the

,combination' with a'locomotive steam engine including a reciprocatingcrosshead. and a steam-distribution valve, a plate secured to saidcrosshead, an eccentric carried by said plate, a lap'and lead leverconnected with said eccentric, a pin and slot connectionprovidedcontiguous to the upper extremity of said lever, and havingconnections with said distribution' valve, a radius rod, pivo ted tosaid leverat a position above said pin and slot connection, and avariable lead arm connected with said radius rod and with saideccentric, and operable to regulate thev substantially verticalpositions of said lever,

V In testimony whereof I afiix my signature.

] THOMAS JAMES, JR.

